I have a Windows 10 desktop. I use File Explorer to copy files from my cameras' SD cards to my hard drive. I use PM's dialog to upload the files to the forum. Works like a champ, except for the fact that the rotation bit is ignored, so that portrait oriented images come in rotated 90 degrees. Years back you had the resize JPG files to stay under about 100kb or the uploader would reject them, but that's no longer a problem. One change that was made a the same time was the way it handles GIF files. I used to be able to upload line drawings as high resolution 2-bit GIF files, now the files get resized to down to the point that they're unusable. Now I have to convert drawings to JPGs to get them to post at a decent resolution.
...
.tiff would be better for line-art, actually. Compression philosophy issue.
.jpg's are compressible, but it is a lossy process.
.png is basically .gif with less legal hassle. And then it was enhanced. Neither as good as .tiff for accurate line-art. PM does
not support .tiff. It isn't as easy, server-side. professional publishing industry relies on it mostly for the "master", puts out the post-edit work in formats that are not as resource-hungry.
PM
DOES support .png - which is close enough to .tiff's goodness for OUR needs.. so you might want to experiment with that for drawings instead of .gif, or .jpeg so as to preserve sharp detail.
...